CH Practice Test

The Certified Hydrographer (CH) exam is for hydrographic survey practitioners seeking certification through the National Society of Professional Surveyors (NSPS). This page brings together free practice sets, the official content areas, explained sample answers, and application requirements to help you organize your preparation. Practice Test Geeks uses AI tools to write its content; the sample questions are practice material, not real exam questions.

CH Exam at a Glance

What changed for CH in 2026

• Oct 27, 2026: Testing window changed to Any time at NSPS HQ (Frederick, MD); also at each biennial U.S. Hydrographic Conference (previously Any time at NSPS HQ (Frederick, MD); also at each U.S. Hydrographic Conference (odd-numbered years)).^[1]
• Oct 27, 2026: Exam fee changed to $150 exam fee (plus $50 application fee) (previously $50 application fee (nonrefundable) + $150 exam fee).^[1]
• Oct 27, 2026: Number of questions changed to 160 multiple-choice questions (previously 160 multiple-choice questions (open book)).^[1]
• Oct 27, 2026: Eligibility changed to 60 months survey experience (or 24 mos + Cat A / 36 mos + Cat B); 24 mos technical charge; 24 mos field; S-5B coursework; logbook; project report; 4 references (previously 60 months of hydrographic survey experience (or 24 months + IBSC Cat A, or 36 months + IBSC Cat B); IHO S-5B coursework; logbook, project report, 4 references).^[1]
• Oct 27, 2026: Retake policy changed to Reapply after 12 months; unlimited attempts (previously Reapply after 12 months if denied; no limit on attempts).^[1]
• Oct 27, 2026: Validity changed to 2 years (previously 2-year certification period).^[1]
• Oct 27, 2026: Renewal changed to Every 2 years: $100 fee and 30 PDHs (previously Every 2 years: $100 fee + 30 PDH).^[1]

What the CH is and how it works

According to National Society of Professional Surveyors, “The Certified Hydrographer examination lasts three (3) hours and consists of one hundred sixty (160) multiple choice questions and will test knowledge in the six (6) categories of the IHO Standards of Competence for Hydrographers.”^[1]

The Certified Hydrographer examination assesses knowledge across the hydrographic subject areas in the NSPS program outline. It is an in-person, proctored, open-book examination with 160 multiple-choice questions and a 3-hour time limit. The supplied official information does not state a passing score or explain how scores are calculated. Consult the NSPS certification program book for official requirements.

Eligibility includes 60 months of hydrographic survey experience, or a recognized Category A qualification with 24 months of experience, or Category B with 36 months. Requirements also include 24 months in technical charge, 24 months of field experience, S-5B coursework, a logbook, a project report, and 4 references. Check the program book when assembling evidence for your application.

The exam fee is $150, plus a $50 application fee. Testing is available by arrangement at NSPS headquarters in Frederick, Maryland, and at each biennial U.S. Hydrographic Conference. The listed March 22–25, 2027 dates are the conference dates; confirm the actual examination appointment with NSPS.

Certification is valid for 2 years. Renewal requires a $100 fee and 30 PDHs. The program book allows applicants denied certification to reapply after 12 months from the denied application's submission date, with unlimited reapplications. That wording concerns denied certification applications; confirm how it applies to an unsuccessful examination before arranging another attempt.

CH content outline and where to practise each area

The content areas below are copied from the official CH content outline published by National Society of Professional Surveyors, with the share of the exam each area carries. The right-hand column shows which of our practice sets covers it.

Worked examples: how to reason through CH questions

These are practice questions written for this site, not questions from the real exam. Each explanation shows why the right answer is right and why the others are wrong.

Example 1

Question: What is the principle of least privilege in CH technology?

1. Users get only the minimum access needed for their role
2. All users get administrator access
3. Access based on seniority
4. Everyone shares credentials

Answer: A. Users get only the minimum access needed for their role

Explanation:

A is correct: least privilege means giving users only the access necessary for their role. This limits the damage that an accidental action or compromised account can cause. B is wrong because administrator access grants broad powers that ordinary tasks may not require. C is wrong because seniority does not establish which permissions a task needs. D is wrong because shared credentials weaken accountability and prevent access from being controlled separately for each user. Remember: assign permissions according to the work someone must perform. This question addresses general access control; it should not substitute for studying the listed hydrographic content areas.

Example 2

Question: Why is documentation critical in CH compliance?

1. It provides evidence of compliance and defensible records
2. It creates unnecessary paperwork
3. Only for tax purposes
4. Optional for experts

Answer: A. It provides evidence of compliance and defensible records

Explanation:

A is correct: documentation provides evidence that requirements were met and preserves records that can be examined if compliance is questioned. A defensible record connects the requirement with what was done and the evidence supporting it. B is wrong because describing records as unnecessary paperwork ignores their evidential purpose. C is wrong because compliance documentation is not restricted to tax matters. D is wrong because a person's experience does not remove the need for verifiable records. Remember: a claim of compliance needs supporting evidence. Documentation makes that evidence available for checking rather than leaving the claim dependent on memory or assertion.

Example 3

Question: What is the purpose of a datum transformation?

1. To project 2D maps
2. To increase map scale
3. To switch between ellipsoids
4. To smooth elevation data

Answer: C. To switch between ellipsoids

Explanation:

C is the intended answer, but its wording is too narrow. A datum transformation converts coordinates from a source geodetic datum to a target datum. It can involve differences in reference ellipsoids, but datums can also differ while using the same ellipsoid. Treat “switch between ellipsoids” as the closest available option, not a full definition. A is wrong because a map projection expresses positions on a plane; it does not itself define a change of datum. B is wrong because increasing map scale changes the display, not the reference datum. D is wrong because smoothing modifies data variation. Remember: identify the source and target datums before combining coordinates.

How to use these practice tests

Start with the NSPS certification program book. Compare its requirements with your experience records, coursework, logbook, project report, and references so application preparation does not get lost behind question practice. Use the official content areas as your study checklist.

Begin subject practice with Bathymetric Data Acquisition & Processing, then work through Geodesy & Coordinate Systems and Tides, Water Levels & Vertical Datums. For each error, record the concept you misunderstood and locate the supporting explanation in your reference material. Explain why the other options fail before retrying the question.

Use Hydrographic Survey Standards & Quality Control and Navigation & Nautical Chart Production to address their related areas. Study seafloor imagery from the official material because this page has no directly matched set. Treat broader environmental and technology sets as supplementary material, rather than evidence of exam coverage.

Prepare for the open-book format by organizing your references and practising how to locate definitions and procedures. Confirm reference-material rules and your testing appointment with NSPS before test day.

Sources & last verified

1. National Society of Professional Surveyors — number of questions, time limit, exam fee, retake policy (official source). “The Certified Hydrographer examination lasts three (3) hours and consists of one hundred sixty (160) multiple choice questions and will test knowledge in the six…” Verified Oct 27, 2026.
2. thsoa.org — next exam date (official source). “US Hydro 2027 22 - 25 March 2027Wilmington Convention Center, North Carolina” Verified Oct 27, 2026.
3. cdn.ymaws.com — other (official source). “bathymetry - 56 35%” Verified Oct 27, 2026.

How we verify: editorial & fact-checking policy. Report an error: contact us.